SUMATRAN RHINOS

• Dicerorhinus sumatrensis 

"Dicerorhinus”: from the Greek di, meaning “two” and “ceros”, meaning “horn” and “rhinos”, meaning “nose” and “sumatrensis” referring to Sumatra

• Western Sumatran rhino (Dicerorhinus sumatrensis)

• Eastern (Borneo) Sumatran rhino (Dicerorhinus sumatrensis harrissoni)

• Northern Sumatran rhino (Dicerorhinus sumatrensis lasiotis)

• Western: Critically endangered

• Eastern (Borneo): Listed as critically endangered by the IUCN, but only two or three are believed to exist

• Northern Sumatran: Assumed extinct

• The exact number is unknown.  The Indonesian government's official estimate is 80 individuals. However, the African rhino specialist Group estimates the actual figure is closer to 34-47 (correct as of September 2023).

• The eastern (Borneo) Sumatran rhino was declared extinct in the wild in Malaysian Boneo in April 2015.  There are thought to be 2 or 3 left in Kalimantan, the Indonesian side of Borneo including a captive female named Pahu.  

•  An internal assessment carried out by the Asian Rhino Specialist Group (AsRSG) estimates the population has declined around 13% between 2017 and 2022.  Their inhospitable habitat, low numbers and fragmented population complicate tracking and conserving, but also mating.

• Current range: Only found on the Indonesian island of Sumata (except the 2 or 3 in Kalimantan) at Way Kambas National Park, Leuser Ecosystem and Bukit Barisan National Park, Sumatra

• Habitat: Dense tropical forest, both lowland and highland, preferring swamps and areas of dense vegetation

• Diet: Twigs, leaves, shrubs and fruit (especially wild mangoes and figs)

• Once prevalent in the foothills of the eastern Himalayas, India, Bhutan, Bangladesh, Myanmar, Laos, Thailand, Malaysia, Indonesia and southwestern China as well as the Indonesian islands

• Approximately 30-40 years although a female Sumatran rhino called Bina celebrated her 42nd birthday in January 2023.

• Dark orange-red-brown skin colour with short, bristly hair which helps mud cake their bodies to protect their skin.

• Captive rhinos have a denser covering of hair due to less abrasion from vegetation

• Calves are born with a dense covering of hair which turns darker and becomes more bristly as they age

• Two distinctive skin folds before the front and after the hind legs

• They're adept at negotiating steep slopes and mountains

• Weight: 500-950 kg

• Body length: Up to 250 cm

• Height (to shoulder): 120-150 cm

• Gestation: 15-16 months

• Birth numbers: Single calf

• Birth interval: 3-4 years

• Female sexual maturity: 6-7years

• Male sexual maturity: 10 years

• Usually solitary, except for females with small calves and brief periods of courtship

• Males have territories up to a range of 50 km²

• Arguably the most voiciferous of the rhino species, with a wide selection of sounds including eeps, whale and whistle-blows which contain high level infrasound that would be advantageous for use in the rhino's forest habitat

• Front horn:  25-80 cm

• Rear horn: Approximately 10 cm